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URL of this page: https://medlineplus.gov/druginfo/meds/a682381.html

Erythromycin

pronounced as (er ith roe mye' sin)

Why is this medication prescribed?

Erythromycin is used to treat certain infections caused by bacteria, such as infections of the respiratory tract, including bronchitis, pneumonia, Legionnaires' disease (a type of lung infection), and pertussis (whooping cough; a serious infection that can cause severe coughing); diphtheria (a serious infection in the throat); sexually transmitted diseases (STD), including syphilis; and ear, intestine, gynecological, urinary tract, and skin infections. It also is used to prevent recurrent rheumatic fever. Erythromycin is in a class of medications called macrolide antibiotics. It works by stopping the growth of bacteria.

Antibiotics such as erythromycin will not work for colds, flu, or other viral infections. Taking antibiotics when they are not needed increases your risk of getting an infection later that resists antibiotic treatment.

How should this medicine be used?

Erythromycin comes as a capsule, tablet, delayed-release (releases the medication in the intestine to prevent break-down of the medication by stomach acids) capsule, delayed-release tablet, and an oral suspension (liquid) to take by mouth. It usually is taken with or without food every 6 hours (four times a day), every 8 hours (three times a day), or every 12 hours (twice a day). Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take erythromycin exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

Shake the suspension well before each use to mix the medication evenly.

If you are taking the suspension, do not use a household spoon to measure your dose. Use the measuring spoon, dropper, or cup that came with the medication or use a spoon made especially for measuring medication.

Swallow the capsules and tablets whole with a full glass of water; do not chew or crush them.

Continue to take erythromycin even if you feel well. Do not stop taking erythromycin without talking to your doctor.

Other uses for this medicine

Erythromycin is also used sometimes used to prevent heart infection in people having dental or other procedures. Talk to your doctor about the possible risks of using this medication for your condition.

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

What special precautions should I follow?

Before taking erythromycin,

  • tell your doctor and pharmacist if you are allergic to erythromycin, any other medications, or any of the ingredients in erythromycin capsules, tablets, or suspension. Ask your pharmacist or check the manufacturer's patient information for a list of the ingredients.
  • tell your doctor if you are taking astemizole (Hismanal) (not available in the U.S.), cisapride (Propulsid) (not available in the U.S.), dihydroergotamine (DHE 45, Migranal), ergotamine (Ergomar, in Cafergot, in Migergot), pimozide (Orap), or terfenadine (Seldane) (not available in the U.S.). Your doctor will probably tell you not to take erythromycin if you are taking one or more of these medications.
  • tell your doctor and pharmacist what prescription and nonprescription medications, nutritional supplements, and herbal products you are taking or plan to take. Be sure to mention any of the following: alprazolam (Xanax), amlodipine (Norvasc, in Caduet, in Lotrel), anticoagulants ('blood thinners') such as warfarin (Coumadin, Jantoven), bromocriptine (Cycloset), carbamazepine (Carbatrol, Epitol, Equetro, Tegretol), cilostazol (Pletal), colchicine (Colcrys, Mitigare), cyclosporine (Neoral, Sandimmune), digoxin (Lanoxin), diltiazem (Cardizem, Cartia, Diltzac, Tiazac), disopyramide (Norpace), dofetilide (Tikosyn), lovastatin (Altoprev), midazolam, phenytoin (Dilantin, Phenytek), procainamide (Procanbid), quinidine, sildenafil (Revatio, Viagra), simvastatin (Zocor, in Vytorin), sotalol (Betapace), valproic acid (Depakene, Depakote), verapamil (Calan, Covera, in Tarka, Verelan). theophylline (Elixophyllin, Theochron, Theo-Dur), and triazolam (Halcion). Many other medications may also interact with erythromycin, so tell your doctor about all the medications you are taking, even those that do not appear on this list. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
  • tell your doctor if you have or have ever had prolonged QT interval (a rare heart problem that may cause fainting or irregular heartbeat), an irregular heartbeat, low levels of magnesium or potassium in your blood, or liver disease.
  • tell your doctor if you are pregnant, plan to become pregnant, or are breastfeeding. If you become pregnant while taking erythromycin, call your doctor.
  • if you are having surgery, including dental surgery, tell the doctor or dentist that you are taking erythromycin.

What special dietary instructions should I follow?

Unless your doctor tells you otherwise, continue your normal diet.

What should I do if I forget a dose?

Take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.

What side effects can this medication cause?

Erythromycin may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

  • upset stomach
  • diarrhea
  • vomiting
  • stomach pain
  • loss of appetite

Some side effects can be serious. If you experience any of the following symptoms, call your doctor immediately or get emergency medical treatment:

  • rash
  • itching
  • hives
  • difficulty breathing or swallowing
  • wheezing
  • yellowing of the skin or eyes
  • dark urine
  • pale stools
  • unusual tiredness
  • pain in the upper right part of the stomach
  • seizures
  • fast, pounding, or irregular heartbeat
  • severe diarrhea (watery or bloody stools) that may occur with or without fever and stomach cramps (may occur up to 2 months or more after your treatment)

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

What should I know about storage and disposal of this medication?

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom).

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach. http://www.upandaway.org

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website (http://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.

In case of emergency/overdose

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

What other information should I know?

Keep all appointments with your doctor and the laboratory. Your doctor will order certain lab tests to check your response to erythromycin.

Do not let anyone else take your medication. Your prescription is probably not refillable. If you still have symptoms of infection after you finish the erythromycin, call your doctor.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

Brand names

  • EES®
  • ERY-C®
  • Ery-Tab®
  • Erythrocin®
  • PCE®
  • Pediamycin®

This branded product is no longer on the market. Generic alternatives may be available.

Last Revised - 09/15/2019